Abstract: A turbine exhaust case (TEC) has an outer case and an inner case structurally interconnected by a plurality of circumferentially spaced-apart struts. At least one of the struts has an airfoil body with a hollow core. The airfoil body has opposed pressure and suction sides extending chordwise from a leading edge to a trailing edge and spanwise from a radially inner end to a radially outer end. The radially inner end of the strut has a strut wall extension that extends through the inner case to a location radially inward of the inner case relative to the central axis.

Abstract: A gas turbine engine has a housing exposed to a high temperature environment. The housing has a circumferential wall extending around the engine centerline and circumscribing an oil cavity. The wall has a sealing interface at an inner diameter thereof, the sealing interface having a central axis offset from the engine centerline. A boss is formed on the wall on the offset side relative to the engine centerline and a probe is mounted to the boss. The probe projects into the oil cavity. The oil in the oil cavity thermally shields the probe from the high temperature environment.

Abstract: A gas turbine engine has: an engine shaft rotatable about a rotation axis; at least two bearings spaced apart from one another along the rotation axis, the at least two bearings having inner races for rotation with the engine shaft, outer races, and rolling elements disposed radially between the inner races and the outer races; a bearing support extending axially along the rotation axis from one of the at least two bearings to the other, the bearing support secured to both of the outer races of the at least two bearings, the bearing support secured to a structural case of the gas turbine engine via frangible tabs.

Abstract: A bearing housing for a gas turbine engine has first and second housing members axially telescoped into each other at a slip joint. The first and second housing members extend circumferentially around a central axis for circumscribing a bearing cavity. The first housing member has a first bearing support for supporting a first bearing in the bearing cavity. The second housing member has a second bearing support for supporting a second bearing in the same bearing cavity. A seal is provided at the slip joint for sealing the bearing cavity.

Abstract: A secondary air system for an aircraft engine comprises an air flow path communicating between a source of pressurized cooling air and an air consuming component. A filter is disposed in the air flow path upstream from the air consuming component. The filter has at least one of: openings of a size selected for capturing suspended particles; and a filter surface material for binding with chemical contaminants.

Abstract: A casing assembly includes first case with a first case body at least partially disposed in a hot section. The first case body has a first case flange and the first case body adjacent to the first case flange is resiliently deformable. A second case downstream of the first case has a second case body with a second case flange extending radially outwardly to a radially-outer wall defining an outer diameter of the second case flange. The first case flange abuts the radially-outer wall of the second case flange. The second case has struts extending radially from an inner end to an outer end. The leading edge portion at the outer end of each of the struts has an axial position defined along the center axis that is similar to an axial position of the second case flange.

Abstract: A gas turbine engine exhaust system comprises an instrumented exhaust duct including a set of exhaust temperature probes installed at the exhaust end of the duct in an air space between the engine outer case and a surrounding engine nacelle. A shield is removably installed at the end of the exhaust duct to protect the probes and associated wiring in the air space.

Abstract: There is disclosed a gas turbine engine including a bearing housing having at least two bearings axially spaced from one another relative to a central axis. The bearing housing includes an axially deformable bellows between the bearings configured to permit axial relative movement of the bearings. A method of operating a bearing assembly is also disclosed.

Abstract: A turbine exhaust case (TEC) includes an outer case, an inner case, and a plurality of struts structurally connecting the inner case to the outer case. At least one of the struts has an airfoil body with a hollow core. A leading edge stiffener is provided at the radially inner end of the airfoil body. The leading edge stiffener projects into the hollow core and merges with a stiffener ring projecting from a radially inner surface of the inner case.

Abstract: A through-flow gas turbine engine includes a core comprising multiple spools rotatable about a center axis. An accessory gearbox (AGB) is drivingly engaged to the core and disposed aft of the outlet. A reduction gearbox (RGB) is drivingly engaged to the core and disposed forward of the inlet. The RGB has an RGB output to provide rotational output to a rotatable load. An electric motor is drivingly engaged to the rotatable load. An electric generator is configured to provide electrical power to the electric motor. the electric motor and the electric generator are disposed axially adjacent one another, and axially between the outlet and the AGB.

Abstract: A thermal shielding arrangement for a turbine probe comprises a heat shield having first and second mating portions axially engaged in overlapping relationship around a probe extending through an air cavity between an exhaust case and a turbine housing. The first mating portion is provided on a radially outer surface of the turbine housing. The second mating portion projects radially inwardly from a radially inner surface of the exhaust case.

Abstract: A gas turbine engine exhaust system comprises an instrumented exhaust duct including a set of exhaust temperature probes installed at the exhaust end of the duct in an air space between the engine outer case and a surrounding engine nacelle. A shield is removably installed at the end of the exhaust duct to protect the probes and associated wiring in the air space.

Abstract: A twin-engine system includes a gas turbine engine comprising a core and a first output shaft drivable by the core. An electric engine has an electric motor configured to drive a second output shaft. A reduction gear box (RGB) has an RGB input drivingly engaged to both the first output shaft and the second output shaft. The RGB has an RGB output to provide rotational output to a rotatable load.

Abstract: A gas turbine engine has a bearing housing mounted to structure linked to the engine mounting pads. The bearing housing has bearing housing flanges with bearing housing flange openings aligned with attachment flange openings of the structure. Some of the bearing housing flange openings are slots. A first group of fasteners extends through one of the attachment flange openings and through one of the bearing housing flange openings. A second group of fasteners extends through one of the attachment flange openings and through one of the slots. The first group of fasteners are sacrificial fasteners configured to fracture in response to a load on the bearing housing exceeding a fracture load. The bearing housing is displaceable relative to the structure after fracture of the sacrificial fasteners via the second group of the fasteners moving within and relative to respective ones of the slots.

Abstract: The gas turbine engine can have a structure for holding bearings within a casing, with a shaft being rotatably mounted to the casing via the bearings and via the structure, the structure having a first wall segment and a base structure receiving the bearings, the first wall segment having a proximal end structurally joined to the base structure, the first wall segment extending away from the base structure, and having a portion extending at least partially axially and thereby being radially flexible relative to the second wall segment, the structure providing both structural resistance and radial stretchability.

Abstract: A through-flow gas turbine engine includes a core comprising multiple spools rotatable about a center axis. An accessory gearbox (AGB) is drivingly engaged to the core and disposed aft of the outlet. A reduction gearbox (RGB) is drivingly engaged to the core and disposed forward of the inlet. The RGB has an RGB output to provide rotational output to a rotatable load. An electric motor is drivingly engaged to the rotatable load. An electric generator is configured to provide electrical power to the electric motor. One of the electric motor and the electric generator is disposed axially between the outlet and the AGB and the other of the electric motor and the electric generator is disposed axially between the inlet and the RGB.

Abstract: A bearing housing for a gas turbine engine has first and second housing members axially telescoped into each other at a slip joint. The first and second housing members extend circumferentially around a central axis for circumscribing a bearing cavity. The first housing member has a first bearing support for supporting a first bearing in the bearing cavity. The second housing member has a second bearing support for supporting a second bearing in the same bearing cavity. A seal is provided at the slip joint for sealing the bearing cavity.

Abstract: A variable guide vane (VGV) assembly, has: a casing enclosing a cavity and defining apertures distributed around a central axis; variable guide vanes (VGVs) distributed around the central axis and having an airfoil portion extending from a first end to a second end along a pivot axis, and a shaft portion pivotably received within the apertures; vane drive members secured to the shaft portions of the VGVs and located within the cavity, a unison transmission member within the cavity and rotatable about the central axis and engaged to the vane drive members, and an external mechanism secured to the second end of one of the VGVs and disposed outside the cavity, the external mechanism engageable by an actuator for rotating the one of the VGVs about its pivot axis, thereby rotating the unison transmission member, which, in turn, drives a remainder of the VGVs in rotation.

Abstract: The gas turbine engine can have a rotary shaft mounted to a casing via a bearing housed in a bearing housing, for rotation around a rotation axis, a gas path provided radially externally to the bearing housing, a feed pipe having a radial portion extending from an inlet end, radially inwardly across the gas path and then turning axially to an axial portion leading to an outlet configured to feed the bearing housing, the axial portion of the feed pipe broadening laterally toward the outlet.

Abstract: A thermal shielding arrangement for a turbine probe extending through an exhaust case and a turbine housing of a gas turbine engine comprises a sleeve having a radially inner end fixedly mounted to the turbine housing and a radially outer end floatingly received in a probe boss on the exhaust case. The radially outer end of the sleeve opens to an air cavity between the exhaust case and a surrounding engine nacelle to allow for air circulation around the probe.